Japanese Patent Application Publication No. H8-142790, Japanese Patent Application Publication No. H11-152004, and Japanese Patent Application Publication No. H11-180243 disclose prior-art techniques related to vehicle side airbag devices, which include taking up a side airbag obliquely with respect to the vertical direction and spreading the side airbag upward in the process of deployment and inflation.
The airbag device for side collision disclosed in Japanese Patent Application Publication No. H8-142790 is aimed to deploy an airbag quickly after detection of a side collision, and the airbag is folded into a long band shape in the deployment direction and in a spirally rolled state while its surface, which is to face the vehicle interior side wall during deployment, is positioned outside, and the airbag is adapted to be deployed forward as its outer side surface is abutted against the vehicle interior side wall and the rolled state is unfolded upon a side collision.
The structure and method for folding an airbag in Japanese Patent Application Publication No. H11-152004 is directed to the object of providing a structure and method for folding an airbag that allows improved deployment speed and smooth deployment behavior to be obtained, and here, a head protection portion is rolled a number of times while its protection surface faces inside, the head protection portion is pushed into a chest protection portion, and at this time, part of the chest protection portion coupled to the head protection portion is pushed into the chest protection portion.
The airbag device for side collision disclosed in Japanese Patent Application Publication No. H11-180243 is aimed to provide an airbag device for side collision capable of providing a folded airbag near an upper end of the backrest of a seat without preventing smooth inflation of the airbag, and the airbag device for side collision has the folded airbag on the upper side of the backrest of the seat. The airbag is attached and fixed to the seat frame in a plurality of locations in the vertical direction on the rear edge side and has a lower chamber upstream of inflation gas and an upper chamber provided above the front side of the lower chamber, and the airbag is stored in a folded state and adapted to project forward and deployed upward during inflation. The airbag is provided with radial folding lines around the upper part side of the lower chamber on the rear edge side, and the upper chamber and the lower chamber are folded in a sector shape and stored on the rear edge side of the lower chamber.